However many fans don't believe there's anything wrong with Harry and Meghan's comment, pointing out that they did the same thing for Princess Charlotte and Prince Louis's birthdays.

However the message for William was much more formal than the ones they sent to their niece and nephew.

Previous comments had featured warm messages such as "lots of love" and contained kisses and emojis, but this one noticeably did not.

The birthday message came the day after Meghan and Harry revealed they were splitting from the Royal Foundation, the Fab Four's charity.

Kate and William will continue the original charity while the Sussexes set up their own, new foundation.
Many royal fans have accused Harry and Megan of snubbing Prince William (Photo: Courtesy)

The charity split statement says both couples are "incredibly proud of what they have achieved together" but claims the new structure will "best support Their Royal Highnesses with future charitable activity".

However many fans were worried this is another sign of a growing rift between the two royal couples.

The charity split is the latest way the two couples are cutting their ties to each other.

Last year Meghan and Harry split from the Kensington Palace household, setting up their own office within Buckingham Palace.

Before Archie was born, the couple moved out of their palace home, which was just a few doors up from Kate, William, George, Charlotte and Louis, and set up their new life in Windsor at Frogmore Cottage.
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